In 2014 and 2015, Musgrove played for the South Sydney Rabbitohs' NYC team, although for the majority of 2015, he played for the North Sydney Bears in the New South Wales Cup. He finished that year with 13 games and scoring 1 try for North Sydney.
2016 season
In round 1 of the 2016 NRL season, Musgrove made his NRL debut for South Sydney against the Sydney Roosters. In November, he extended his contract with South Sydney from the end of 2017 until the end of 2020.
2017 season
Musgrove made 21 appearances for Souths in the 2017 NRL season but his team failed to make the finals for the second straight season.
2018 season
In the 2018 season, injuries and suspension prevented Musgrove from making a single appearance for Souths, playing twice for their feeder club, the North Sydney Bears, instead. He was suspended from club activities following a domestic violence charge, but that was lifted after he indicated his intention to plead not guilty. He was ultimately charged with property damage, which was overturned on appeal. In November the West Tigers announced they had signed Musgrove for three years. He was released from his contract with the Souths, and began pre-season training with the Tigers. In December, Musgrove was charged with indecent assault for an alleged incident at the Coogee Bay Hotel that occurred two days after he signed with the Wests Tigers. In January 2019 he pleaded not guilty.
2019 season
On 1 March, the NRL announced that they had refused to register Musgrove's contract until the players legal issues were finalized. A statement from the NRL read "A request by the Wests Tigers to register Zane Musgrove, who is currently facing indecent assault charges, has been refused until the case is concluded". On 29 November, it was announced that Musgrove was allowed to resume training with the Wests Tigers after being cleared by the NRL.
Assault allegations
In May 2018 Musgrove was involved in an argument with his former girlfriend, and on July 11, faced charges of common assault, common assault domestic violence related, and intentionally or recklessly destroy/damage property. Musgrove pleaded not guilty. On 19 September, Musgrove pleaded guilty to damaging property and was fined $1,100 and ordered to pay $500 to fix the gate which Musgrove damaged after having an argument with his girlfriend. Musgrove also faced charges of domestic violence related common assault and assault, but both charges were withdrawn by prosecutors. In November Musgrove's sentence was overturned on appeal, and he was given a conditional release order and required to be on good behaviour. In December 2018, Musgrove was charged by police for allegedly assaulting a woman at the Coogee Bay Hotel. Musgrove and Liam Coleman, son of former Souths player Craig Coleman were charged with an act of indecency and aggravated indecent assault. A woman made a complaint to security and a further complaint was made to Eastern Beaches police local area command. Musgrove attended Maroubra police station later that week where he was granted conditional bail. In January 2019 he pleaded not guilty to aggravated indecent assault, indecent assault and common assault. On 21 October 2019, Musgrove was found guilty of assault with an act of indecency and sentenced to a 12-month intensive corrections order.
